If it feels like your morning coffee isn’t giving you the jolt of energy it used to, your tolerance may be to blame. You can get your caffeine tolerance back to normal levels in about two weeks, but you’ll need to wean yourself off of it.

Red Bull may give you wings, but at what cost? To some, energy drinks are dangerous elixirs, while others consider them magic potions of vitality? The truth about how they affect your body is not so black and white.